Production of dinonylnaphthalene sulfonates



United States Patent Office 3,075,005 PRGDUC'HQN 6F DENQNYLNAPHTHALENE SULFUNATES The present invention relates to the production of oilsoluble sulfonates. More particularly, it relates to a process for producing dinonylnaphthalene sulionates of high purity in good yields.

The use of oil-soluble sulfonates as detergents in lubricating oils has been practiced for several years. Initially, the mahogany sulfonates were used almost exclusively. More recently, sulionates of postdodecylbenzene, which is a by-product of the manufacture of dodecyl-benzene, have been used. Both of these materials, when subjected to proper treatment, have been very satisfactory for this purpose. However, the demand for oil-soluble sulfonates has been increasing at such a rate that it would be advantageous to have available other oil-soluble sulfonates. Sulfonates derived from the diaikylnaphthalenes, and in particular those having molecular weights in the range of dinonylnaphthalene and above, are particularly suitable for use as detergents in lubricating oils.

Among the desirable features for a process for producing oil-soluble sulionates are (1) a good yield, in order that the process be economical, and (2) high purity, in order that the product be satisfactory for lubricating oil detergents. It is particularly desirable to have available a sulfonate which is satisfactory for producing overbased detergents by the process of US. Patent No. 2,861,- 951 issued November 25, 1958, to Robert L. Carlyle. The prior art processes, when applied to dinonylnaphthalene as the sulfonating stock, have been deficient in at least one of these requirements.

It is an object of the present invention to provide a process for the production of dinonylnaphthalene sulfonates in good yields. It is another object of the present invention to provide a process for the production of dinonylnaphthalene sulfonates having a high purity. It is still another object of the present invention to provide a process for the production of dinonylnaphthalene sulfonates suitable for the preparation of over-based detergents. Other objects and advantages of the invention will become apparent from the following description thereof.

Broadly stated, the present invention provides a process for the production of dinonylnaphthalene sulfonates, in which the process comprises the steps of:

'(a) Sulfonating dinonylnaphthalene, dissolved in a nonarornatic hydrocarbon solvent having a boiling point less than 150 C, with a sulfonating agent.

(b) Quenching the reaction mixture with from 0.09 to 0.18 part of water per part of sulfonating agent,

(c) Dilution of the reaction mixture with a nonaromatic hydrocarbon solvent to a total of 2.5 to 4.5 parts of solvent per part of dinonylnaphthalene,

(d) Allowing the reaction mixture to stratify and removing the sludge,

-(e) Neutralizing the sulfonic acid with a base,

'(3) Washing the solution of sulfonate with water,

(g) Allowing the aqueous and hydrocarbon layers to stratify and removing the aqueous layer,

(h) Removing solvents and residual water from the dinonylnaphthalene sulfonate.

Before proceeding to specific examples which illustrate our invention, it might be better, first, to define the materials and operating conditions or our invention. For rea- 3,075,05 Patented Jam. 22, 1963 son of brevity, dinonylnaphthalene will often be referred to as DNN hereafter.

The dinonylnaphthalene which We prefer to use as a sulfonating stock is prepared by the alkylation of nonene and naphthalene. The nonene used in the alkylation is not a pure compound, but a mixture of olefins. The preferred material is a oy-product of the polymerization of propene using a phosphoric acid-kieselguhr catalyst at about 1000 p.s.i.g. and 400 F. The catalytic polymerization of propylene resulting in the formation of lay-product none'ne is illustrated in the patent to Grote et al., US. Patent No. 2,457,146, the nonene being described therein as low-boiling polymer (C6-C12) a portion of which is recycled through line 32 and the remainder of which is withdrawn through line 33. The true nonene portion is highly branched and contains tertiary carbon atoms. The following physical properties are typical of the nonene used:

Mass spectrometer analyses of two typical nonene samples are given in Table I.

TABLE 1 Mass Spectrometer Analyses of Typical Nonene Samples Sample (liquid volume 1 ant) A B 35 and less fi. CT- 7.2 7. 0 Cs. 12.8 14. 7 09-.-. 45. 3 55. 5 010.- 23.1 19.1 011- 5. 4 3. 4 0. 5 0. 3

in the prepartion of the DNN the material distilling above 250 C. at 20 mm. Hg pressure is the desired DNN. A. representative distillation curve of the DNN is shown in Table II.

TABLE II Distillationof Typical DNN Samples [20 mm. Hg pressure] Sample A B G Gravity, API 21. 8 22. 2 22 6 5% 400 409 300 10%- 402 414 .590 20%- 404 418 40.5 30% 407 423 408 40%.-.- 410 427 4l2 50% 414 432 415 60%- 419 438 420 707 426 447 427 438 462 440 465 490 468 05% 499 520 497 527 548 520 Recovered, Force 97. 0 97. 5 97. 5

1 A.S.T.M. method D-1160.

A nonaromatic hydrocarbon solvent is used for the DNN. A preferred solvent is hexane, with suitable solvents being pentane and petroleum naphtha which has been treated to remove aromatic constituents. We have found the solvent to DNN ratio is important in both the sulfonation step and the settling step. In order to produce a good quality sulfonate the ratio of total solvent to DNN should be between 2.5 and 4.5 (preferably 4) parts of solvent per part of DNN (weight basis) in the settlingstep. Two methods may beused in arriving: at the desired total solvent to DNN ratio.; In one method alesser amount. of solvent is used in the sulfonation step with, the remainder of the solvent being added in the settlingstep. In this method a minimum of about 1 part 'ofsolvent per partof DNN (weight basis) is used in thesulfonation step. This method gives both a high, yieldgbased on oleum used, and a good quality sulf o'nate. In the second method the same amount of solvent. is, used in both the sulfonat-ionand settling step. This amount of solvent may vary from 2.5 to 4.5 (preferably .4) parts of solvent per part of DNN (weight basis); In this method additional oleum is needed togive yields: comparable. with the first. method. However, a slightly better quality sulfonate is obtained "in this method. 7 suitablesulfonating agents include oleum (10to 50%) and sulfur trioxide, The preferred sulfon-ating agent is 20 percent oleum because of its being readily-available.- The amount of sulfonating agent is preferably from"l.0 to;- 1.5-pa-rts (weight) per: part ofDNN. We--havefound thatin .order...to obtain optimum re-' sults the amount-of waterused in..the quenching stepis important. -Anamountof. waterbelowv aboutv 0.09 part per part of 20 percent oleumis insufficient to quench the reaction and-remove impurities .suificiently. On the other hand :as :the amount-oi- .water is increased. above 0.18 part per part of 20 percent oleum the yieldof sulfonate decreases. When less than optimum results are suitable it is possible to operate outside of the preceding range. When other sulfonating agents are used, the water ratio should be adjusted to give a similar water to 80;; ratio. For; example, the preceding 0.09 part per part of 20% oleum corresponds to about 0.10 part per part of total S Other ratios are proportionate. -The...sulfonation reaction is conducted at a temperature of 40 1 C. or less. The reaction time is not critical. As is,well known to those skilled in. the sulfonation art,

j an.--insuflicient time will give low yields, while an excesstime will cause charting and. decomposition of the sulfonatable material. When our process-is conducted batch-wise; reactiontirnes .of .3, minutes "to "1 hour are suitable.- When-theprocess is conducted .0n. a..continu. .ousibasis withgood agitation, contact times of :a-tew seconds :are suitable.

The basic compoundsxwhich can be usedto neutralize the dinonylnaphthalene sulfonic acid are limitedby the requirements of the water-washing step. Accordingly, they should meet the followingrequirements: (1) their sulfates must be water soluble and -(2) their low-molecular-weight sulfonate;derivatives:must be water solu- -ble.- Preferred basiccompounds arethoseinwhich the cation is an alkali metal or ammonium and in which the anion-is-a hydroxideorv carbonate- The stoichior metric amount, or a slight excess thereof, is used.

- The water washing of the sulfonate is conducted-to remove; low-molecular-weight material which is; water soluble and oil: insolubler The amount ohwatermust be controlled to avoid formingemulsions. j In addition, the-washing must be conducted on a sulfonate, not .a sulfonic acid, to avoid formation. of 'em'ulsiolns'IQ We have found a suitable range" of the-ratio ofwater.to DNN (on a weight basis) to be 2.104, .Witha preferred ratio being in the range of'2.5"to 3.5;

The solvents are removed from the DNN sulfonate by heating to 150 C. The removal of the residual water may tbe'facilitatedby blowingthe product with an inert gasi*(e;g,, nitrogen) during the latterpart of the heating step. n I

Inprder'to;disclosermore clearlythe nature of the present invention and the advantages thereof, reference will hereiriafter be made to certain specific embodiments 'which illustrate'the flexibility of the herein-described process It should be clearly understood, however, that t after water quench; to the indicated ratio.

hexane. solution of sulfonate.

thisis done solely byway of example and is not to be construed as a limitation upon the spirit and the scope of the appended claims.

EXAMPLE 1 This example shows the effect of varying oleum to DNN ratios. The procedurewas as outlined previously, withthe water quench being omitted. The total hexane/ DNN ratio was 4:1. The data are shown in Table III.

TABLE III Efiect of Varying 'Oleum/DNN Ratios oleum/DNN Grams 100% Combining Percent (weight-ratio) Na sulfonate/ weight salt 7 grams DN N EXAMPLE 2 TABLE IV.

Efie'ct of VaryingAmozmts of Water in Quench Water/oleum Grams 100% ratio (welght) Precipitate sulfonate/ W grams DNN.

EXAMPLE 3 Thisexample. .shows the efiect of using hexane dilution: withandwithout the water quench. An oleum/ .DNN ratio-of.1.3.was used. In addition, it shows the eifect..of,.sulfonating inhexane as compared to white oil. The data are shown in Table V.

TABLE V.

Combined Efiectspf Hexane Dilution and Water Quench r1 V W t o i l 0 exane 8. er 10 S11 om- Percent DNN White precipitate oleum tomato/ biniug Salt (weight) grams weight DNN 4.0 Moderatm v 0 1.10 493 2.45 4.0 Very shgh 0.18 1.11 481 0.86 i 1. o eavyo 0. 98 480 5. 68 1 1. 0 slight 0. 18 0. 91 471 1. 32 0 0 .41 5.0 0 1.00

Sulfonate'd at hexane/DN N ratio of 1:1, with subsequent dilution,

d stnlionated at hexane/DN N ratio of 1:1, withno subsequent hexane.

11 10111. Sulfonated. in white. oil (5-1 dilution) with 1.0 part; oleum. Sulfonated in hexane (5-1. dilution) with 1.0 part oleum.

EXAMPLE 4 Thislexample showsthe effect of'water-washing the An oleum/DNN ratio of 1:1 and a water to DNN ratio of 2.67:1 were used in the example. manner are shown in Table VI.

TABLE VI Water-Washing of the Sodium Sulfonate While particular embodiments of the invention have been described, it will be understood, of course, that the invention is not limited thereto, since many modifications may be made; and it is therefore, contemplated to cover by the appended claims any such modifications as fall Within the true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent is:

1. A process for the production of oil-soluble dinonylnaphthalene sulfonate, said process comprising the steps of:

(a) sulfonating dinonylnaphthalene dissolved in 1-4 parts of nonaromatic hydrocarbon solvent, having a boiling point of less than 150 0., per part of dinonylnaphthalene with a sulfonating agent selected from the group consisting of oleum and sulfur trioxide;

(11) quenching the sulfonic acid reaction mixture with an amount of water in the range of about 0.10 to about 0.20 part by weight per part of total S in said sultonating agent;

(0) diluting the Water-quenched reaction mixture with nonaromatic hydrocarbon solvent to a total solvent to dinonylnaphthalene ratio of 2.5 to 4.5 parts of solvent per part of dinonylnaphthalene (weight basis);

(d) allowing the reaction mixture to stratify and removing the sludge;

Data on two products prepared in this (e) neutralizing the sulfonic acid with a basic compound selected from the group consisting of alkali metal hydroxides, alkali metal carbonates, ammonium hydroxide, and ammonium carbonate;

(f) washing the solution of sulfonate with from about 2.5 to about 4 parts of water per part of dinonylnaphthalene;

(g) allowing the aqueous and hydro-carbon layers to stratify and removing the aqueous layer;

(It) removing solvents and residual water from the dinonylnaphthalene sulfonate.

2. The process of claim 1 wherein the sulfonating agent is oleum.

3. The process of claim 1 wherein the nonaromatic hydrocarbon solvent is hexane.

4. The process of claim 1 wherein hydrocarbon solvent is pentane.

5. The process of claim 1 wherein the nonaromatic hydrocarbon solvent is a petroleum naphtha treated to remove aromatic constituents.

6. The process of claim 1 wherein the amount of solvent in step (a) is about 1 part per part of dinonylnaphthalene.

7. The process of claim carbon solvent is hexane.

8. The process of claim carbon solvent is pentane.

9. The process of claim carbon solvent is a petroleum naphtha aromatic constituents.

10. The process of the nonaromatic 6 wherein the aliphatic hydro- 6 wherein the aliphatic hydro- 6 wherein the aliphatic hydrotreated to remove claim 1 wherein the sulfonating agent is sulfur trioxide.

11. The process of claim 10 wherein the solvent of step (a) is hexane.

References Cited in the file of this patent UNITED STATES PATENTS 2,573,675 Bloch et a1. Nov. 6, 1951 2,575,807 Griesinger Nov. 20, 1951 2,652,427 Shultz Sept. 15, 1953 2,764,548 King et a1. Sept. 25, 1956 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, $075,005 January 22, 1963 Robert L., Garden et alo he above numbered pat- It is hereby certified that error appears in t Patent should read as ent requiring correction and that the said Letters corrected below read sulfonates column 6, lines l4, l6 l8 and 21, for t numeral "l" each occnrren'ce read ed and sealed this 3rd day of Se Sign ptember l963 (SEAL) Attest:

ERNEST w. SWIDER DAVID L- LADD Attesting Officer Commissioner of Patents 

1. A PROCESS FOR THE PRODUCTION OF OIL-SOLUBLE DINOYLNAPTHALENE SULFONATE, SAID PROCESS COMPRISING THE STEPS OF: (A) SULFONATING DINONYLNAPHTHALENE DISSOLVED IN 1-4 PARTS OF NONAROMATIC HYDROCARBON SOLVENT, HAVING A BOILING POINT OF LESS THAN 150*C., PER PART OF DINONYLNAPTHALENE WITH A SULFONATING AGENT SELECTED FROM THE GROUP CONSISTING OF OLEUM AND SULFUR TRIOXIDE; (B) QUENCHING THE SULFONIC ACID REACTION MIXTURE WITH AN AMOUNT OF WATER IN THE RANGE OF ABOUT 1.10 TO ABOUT 0.20 PART BY WEIGHT PER PART OF TOTAL SO3 IN SAID SULFONATING AGENT; (C) DILUTING THE WATER-QUENCHED REACTION MIXTURE WITH NONAROMATIC HYDROCARBON SOLVENT TO A TOTAL SOLVENT TO DINONYLNAPHTHALENE RATIO OF 2.5 TO 4.5 PARTS OF SOLVENT PER PART OF DINONYLNAPTHALENE (WEIGHT BASIS); (D) ALLOWING THE REACTION MIXTURE TO STRATIFY AND REMOVING THE SLUDGE; (E) NEUTRALIZING THE SULFONIC ACID WITH A BASIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDES, ALKALI METAL CARBONATES, AMMONIUN HYDROXIDE, AND AMMONIUM CARBONATE; (F) WASHING THE SOLUTION OF SULFONATE WITH FROM ABOUT 2.5 TO ABOUT 4 PARTS OF WATER PER PART OF DINONYLNAPHTHALENE; (G) ALLOWING THE AQUEOUS AND HYDROCARBON LAYERS TO STRATIFY AND REMOVING THE AQUEOUS LAYER; (H) REMOVING SOLVENTS AND RESIDUAL WATER FROM THE DINONLYNAPHTHALENE SULFONATE. 